Improved low-water detector



4ATENT OrmeaN SYLVESTER W. VARREN, OF BROOKLYN, NEW YORK.

IM PROVED. LOW-WATER mDETECTO R.

Specification forming part of Letters Patent No. 36,711l: dated October 2l, 1862.

To aZZ whom t may concern:

Be itknown that I, SYLvEsrER WNVARREN, of Brooklyn, in Kings county, in the State of New York, have invented a new and Improved Valve-Operator; and I do hereby declare that the following, taken in connection with the drawing which accompanies and forms part of this specification, is a description of my invention sufiicient to enable those skilled in the art to practice it.

The nature of my invention consists in the combination and arrangement, substantially that herein described, of a vessel containing mercury within an outer casing so coupled with a boiler or other reservoir containing water and steam that either water or steam, or both, may be present within the space between the mercury-reservoir' and its casing, as in a glass water-gage, and so that when steam is present within said space its heat shall expand the mercury, causingdt to operate against an elastic diaphragm, and by ex? panding it to operate through suitable connections to work a valve for the purpose of sounding an alarm or for letting ott the condensed water from steam-heating pipes, or for various other purposes.

Referring to the drawing, which is a sectional view of an apparatus embodying my invention, c is the mercurial reservoir, which is best made of cast-iron. b is a casing, which surrounds a, and is made steamtight. When the expansionof the mercury is to be employed to open a valve to give alarm that the height of the water in a boiler approaches a dangerous level, the easing is connected with the boiler by two pipes, one, c, from the upper part of the casing, terminating in the steam-space of the boiler, while the other, d,

with the axis of the mercury-reservoir, and

so that a spindle connected with the disk h,

which rests upon a rubber diaphragm, shallbe in contact with the spindle of valve g. It will be seen that the supply of steam to the whistle-pipe will tend to keep the valve 'g closed at all times, so that whenever after g has been raised by the expansion of' the mercury by heat said valve will be closed by the pressure ofthe steam upon it as soon as the mercury is sufficiently cooled, and thereby contracted, so as to assume its normal posi tion within the body of the reservoir a. v

Vhen this apparatus is so connected with a boiler that the juncture of the pipe c with the casing Z) is in a plane with the level below which it is not safe to have the water in the boiler fall, it will be seen that steam will enter the casing b from the boiler, and will heat and expand the mercury, causing it to overflow the reservoir and to distend the diaphragm, raising the spindle-*disk thereupon, and thereby opening valve g, causing the whistle to sound.

This device may be so modified as to cause the valve which is opened thereby to discharge the water of condensation from steampipes employed for heating purposes, for it is evident that the pipes c and d may be so connected with the end of any steam circulation77 that steam or water, or both, may be present in the casing from said circulation, and that' when water only is in the casing the valve controlled by the device may be opened, and when steam is present in the casing the expansion of the mercury thereby caused will close the valve, thus admitting escape of water and preventing escape of steam; but in this arrangement it is to be observed that the arrangement ot' valve g must be reversed from that shown in the drawing, as it must open valve, substantially as and for the purpose set on account of its Weight and be closed by the forth.

action of the expansion of the mercury.

I claim- 1862. The combination of the casing b with the steam and Water pipes c and d, the mercuryreservoir a, and an elastic diaphragm, when arranged so as to operate together to Work a SYLVESTER W. VARREN. In presence of J. B. CROSBY,

yJ. E. FALLoN.

Executed this 20th day of August, A. D,

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